Field of the Invention
The present invention relates to a lens actuator, and more particularly, to a lens actuator of which a manufacturing process is simplified and preventing foreign objects from being introduced thereto during the process.
Description of the Related Art
In general, it is common nowadays for mobile terminals such as mobile phones, PDAs, portable computers to not only transmit text messages and voice data but also image data.
Following this trend, recent mobile communications terminals are standardly equipped with camera modules and are able to transmit image data or allow users to make video calls.
In a camera module provided in a mobile communications terminal, a lens moving device is provided to allow for lens zooming or focusing by moving a lens in the optical direction.
The lens moving device may be divided into three types, i.e., a rotation motor type, a piezoelectric actuator (PZT) type, and a voice coil motor (VCM) type, following the manner in which driving force is generated.
The rotation motor type has a relatively complicated strctural mechanism, since it needs to convert rotary motion into linear motion. The PZT type is advantageous in that it is small and light but is disadvantageous in that it requires a high voltage power source.
The VCM type uses electromagnetic force between a coil through which current flows and the flux of a magnet to directly move a lens barrel having the coil or magnet attached thereto in the optical direction, and has advantages in that it has a simple structure and is operable at low voltage.
However, the existing lens actuator of VCM type requires separation space between a coil and a position sensor, and requires a separate process to electrically connect the coil and the position sensor to a printed circuit board, such that the process is complicated, and reliability is lowered if the assembly tolerance is large.
Further, foreign objects may be generated during soldering to contaminate the inside of the lens actuator, thereby lowering the reliability.
Patent Document 1 discloses a camera module having a structure in which an electromagnetic part and a hole sensor are mounted in a yoke.